**Core Concept:** Nephrotic syndrome is a set of clinical symptoms and signs that result from severe renal proteinuria (> 3.5 g/day). It is characterized by edema, hypoalbuminemia, hyperlipidemia, and hypercoagulability. These symptoms are caused by the loss of proteins in urine, primarily albumin, leading to fluid accumulation and imbalanced plasma proteins.

**Why the Correct Answer is Right:** Nephrotic syndrome is primarily caused by conditions that lead to increased permeability of the glomerular capillary walls, allowing proteins to leak out and into the urine. The correct answer (E) refers to conditions that do not lead to such increased permeability and therefore do not cause nephrotic syndrome.

**Why Each Wrong Option is Incorrect:**

A. Nephrotic syndrome can result from membranous nephropathy, minimal change disease, focal segmental glomerulosclerosis, and other primary glomerular diseases. These conditions directly affect the glomerular capillary walls, increasing permeability and causing nephrotic syndrome.

B. Nephrotic syndrome can also result from secondary causes, such as diabetes, lupus, amyloidosis, and certain medications. While these conditions can lead to nephrotic syndrome, they do not directly affect the glomerular capillary walls, which is the primary mechanism behind the increased permeability in nephrotic syndrome.

C. Nephrotic syndrome is not caused by infections, as these are not directly involved in altering glomerular permeability. However, infections can exacerbate pre-existing nephrotic syndrome or contribute to secondary causes.

D. Nephrotic syndrome is not caused by hypertension, as hypertension is a consequence, rather than a cause, of this condition. While hypertension can worsen glomerular damage and contribute to secondary causes, it does not directly induce glomerular permeability changes.

**Clinical Pearl:** Nephrotic syndrome should be considered in patients presenting with edema, hypoalbuminemia, and hyperlipidemia. Investigating and managing the underlying cause of nephrotic syndrome is critical for patient management and recovery.